Insulating paper aging on-line detection device based on fiber collection and dispersion characteristic analysis

Abstract

The application discloses an online detection device for insulating paper aging based on fiber collection and dispersion characteristic analysis. The online detection device comprises a fiber collection mechanism, an online monitoring mechanism for fiber particles and a fiber dispersion characteristic analysis mechanism. In the scheme, the photosensitive element is used to perform online monitoring on the fiber particles in oil. When the number of fiber particles exceeds the preset value, the fiber dispersion characteristic analysis system is triggered. The fiber is dispersedly dyed. Meanwhile, the automatic zooming camera is used to collect the dispersed color of the fiber. Then, the relationship graph between the dispersed color characteristics of the fiber and the degree of polymerization of the insulating paper which has been constructed in the database is matched. The degree of polymerization of the insulating paper in the transformer is judged. The aging degree of the insulating paper in the transformer is accurately diagnosed. The transformer is timely maintained. The safe and stable operation of the large power transformer is ensured.

Description

Technical Field

[0001] This application relates to the technical field of steel structure engineering construction in industrial buildings, and in particular to an online detection device for aging of insulating paper based on fiber collection and dispersion characteristic analysis. Background Technology

[0002] Currently, most transformers in operation are oil-immersed transformers, and their service life mainly depends on the aging state of the transformer's solid insulation (insulating paper). During the aging process, the insulating paper sheds, forming a large number of free-state fibrous particles. Unlike metal particles, because the fiber density is lower than that of mineral insulating oil, the fibrous particles remain suspended in the transformer oil. Considering that various dielectric losses in operating transformers can cause localized overheating, leading to an increase in the internal structural temperature of the transformer, large transformers typically employ forced oil circulation air cooling (OFAF) or forced oil circulation guided air cooling (ODAF) devices to drive the insulating oil to circulate and cool it. However, the fibrous particles suspended in the insulating oil are affected by the oil flow and permeate the entire transformer. At the same time, fibrous particles with high dielectric constants are prone to polarization under the action of a gradient electric field and move directionally along the electric field direction. During the process of movement and accumulation, they form "micro-needle electrodes," which leads to enhanced distortion of the electric field in the oil at the ends of the fibrous particles. When the distortion field strength exceeds the withstand field strength of the transformer insulation system, partial discharge will occur, seriously threatening the safety of the transformer insulation system and even causing transformer power outages. Therefore, it is necessary to accurately detect the aging degree of solid insulation (insulating paper) of transformers to ensure the safe and stable operation of large power transformers in the power system, which plays a significant role in safeguarding national economic security.

[0003] Current methods for assessing the aging degree of insulating paper mainly fall into two categories: assessment of accompanying products of insulating paper aging and assessment of the degree of polymerization of insulating paper. The assessment of accompanying products of insulating paper aging indirectly evaluates the content of carbon (CO2, CO), hydrocarbon gases (H2, CH4, C2H4, C2H6), and furfural in transformer oil during the aging process. The assessment of the degree of polymerization of insulating paper, on the other hand, directly measures the degree of polymerization. As insulating paper degrades due to aging, the length of its internal linear molecular chains shortens, and the degree of polymerization (DP) decreases, macroscopically manifesting as a decline in mechanical strength. The DP value of insulating paper reflects its aging state and can be used to assess the residual life of transformers. Compared to aging assessment methods based on dissolved gases in oil and furfural content, the DP value is the most direct and effective criterion for characterizing the lifespan of insulating paper.

[0004] Both of these assessment methods currently have significant shortcomings: The assessment method for the accompanying products of insulating paper aging involves multiple pathways for the generation of carbonaceous substances (CO2, CO). Besides insulating paper aging, the oxidative decomposition of insulating oil, partial discharge, and environmental pollution can all generate CO2 and CO gases. Furthermore, the content of hydrocarbon gases (H2, CH4, C2H4, C2H6) and furfural can be partially lost during transformer oil filtration and replacement operations. Therefore, assessment based on the accompanying products of insulating paper aging is prone to error and makes it difficult to accurately determine the aging status of the insulating paper. On the other hand, the method for assessing the degree of polymerization of insulating paper requires power outage and core sampling when directly measuring the degree of polymerization, which is inconvenient. Summary of the Invention

[0005] In view of this, this application provides an online detection device for the aging of insulating paper based on fiber collection and dispersion characteristic analysis, which can accurately and conveniently obtain the aging degree of insulating paper.

[0006] This application provides an online aging detection device for insulating paper based on fiber collection and dispersion characteristic analysis, comprising:

[0007] An online fiber particle monitoring mechanism includes an optical fiber transmitter, an optical fiber receiving probe, an A / D signal conversion unit, and a signal processing unit. The optical fiber transmitter generates emitted light that acts on insulating oil. The optical fiber receiving probe receives emitted light from the optical fiber transmitter and acted upon by the insulating oil. The A / D signal conversion unit converts the optical signal from the optical fiber receiving probe into an electrical signal. The signal processing unit processes the electrical signal into readable data.

[0008] A fiber collection mechanism is used to collect cellulose particles by adsorbing insulating oil through a fiber adsorption membrane;

[0009] The fiber dispersion characteristic analysis mechanism is used to analyze the dispersion color parameters of cellulose particles collected by the fiber acquisition component in order to determine the aging degree of the insulating paper corresponding to the insulating oil.

[0010] Optionally, the online fiber particle monitoring mechanism further includes a fiber particle counting display electrically connected to the signal processing unit, the fiber particle counting display being used to display the readable fiber particle related parameters.

[0011] Optionally, the fiber collection mechanism includes an insulating support for supporting the fiber adsorption membrane, a first sliding pipe on which the insulating support is rotatably mounted, and an electrically operated telescopic brush for sweeping the cellulose particles adsorbed on the fiber adsorption membrane onto a glass slide, wherein the first sliding pipe is slidably disposed on an oil channel.

[0012] Optionally, the fiber collection mechanism further includes a second sliding pipe that can slide on the inner wall of the oil passage. The second sliding pipe is used to press the insulating support into a fully extended state when it slides to a position where the first sliding pipe is located between the second sliding pipe and the inner wall of the oil passage.

[0013] Optionally, the fiber collection mechanism further includes a support for picking up the fiber adsorption membrane supported by the insulating support after the insulating support is pressed to a fully extended state.

[0014] Optionally, the fiber collection mechanism further includes an insulating sealing ring fixed on the oil passage to limit the sliding position of the second sliding pipe.

[0015] Optionally, the fiber dispersion characteristic analysis mechanism includes a fiber spreading rod, a glass slide capable of linear reciprocating motion, a processing liquid container, a refractive liquid container, a miniature automatic polarizer, and a white light source. The fiber spreading rod is used to roll the fibers on the glass slide, and the processing liquid container is used to drop the processing liquid onto the glass slide.

[0016] The refractive liquid is dripped into the container, and the miniature automatic polarizing mirror is used to collect the dispersion color parameters of the cellulose particles on the slide under the illumination of a white light source.

[0017] Optionally, the fiber dispersion feature analysis mechanism further includes an autofocus camera for taking pictures of the dispersion color images collected by the miniature automatic polarizer.

[0018] Optionally, the fiber dispersion feature analysis mechanism further includes a data storage device for storing preset images of the polymerization degree of insulating paper and the dispersion color of fiber particles at different aging levels.

[0019] Optionally, an alarm mechanism is included to generate an alarm when the aging state of the insulation paper inside the transformer is determined to be higher than a preset aging level.

[0020] The above-described online aging detection device for insulating paper based on fiber acquisition and dispersion characteristic analysis first utilizes the excellent light guiding properties of optical fiber to count fiber particles in the oil channel. The fiber particles suspended in the oil...

[0021] Fiber particles can alter the transmittance of optical fibers, affecting the reception of the optical fiber receiving probe. The signal processing unit analyzes the deviation caused by changes in fiber 5 to reflect the content of fiber particles in the insulating oil. When the number of fiber particles exceeds a warning value, the fiber dispersion characteristic analysis system is triggered. This system performs dispersion dyeing on the fibers and simultaneously uses a camera with automatic zoom to capture the fiber dispersion color. This color is then matched with a pre-constructed relationship graph between fiber dispersion color characteristics and the degree of polymerization of insulating paper in the database to determine the degree of polymerization of the insulating paper, ultimately assessing the aging degree of the insulating paper inside the transformer. Attached Figure Description

[0022] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0023] Figure 1 This application provides a structural diagram of an online detection device for embodiments;

[0024] Figure 2 An installation diagram of the oil passage connection device is provided for the embodiments of this application;

[0025] Figure 3 A flowchart for online monitoring of fiber particles is provided for embodiments of this application.

[0026] The components in the diagram are labeled as follows:

[0027] 1-Fiber adsorption membrane box; 2-Oil channel; 3-Second sliding pipe; 4-First sliding pipe; 5-Insulating support; 6-Insulating sealing ring; 7-Support; 8-Electric telescopic brush; 9-Fiber spreading rod; 10-Slide; 11-Processing liquid container; 12-Refractive index liquid container; 13-Automatic focusing camera; 14-Data storage device; 15-White light source; 16-Alarm; 17-Flash lamp; 18-Solar panel; 19-Battery; 20-Fiber optic transmitter; 21-Fiber optic receiver probe; 22-Miniature automatic polarizer; 23-Oil conservator; 24-Online detection device; 25-Transformer. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0029] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0030] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0031] The following disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0032] Please refer to Figure 1 The embodiments of this application provide an online detection device for aging of insulating paper based on fiber collection and dispersion characteristic analysis, which includes a fiber collection mechanism, an online fiber particle monitoring mechanism, a fiber dispersion characteristic analysis mechanism, an alarm mechanism, and a power supply mechanism.

[0033] The fiber collection mechanism includes an insulating support 75 for supporting the fiber adsorption membrane, a first sliding pipe 4 on which the insulating support 75 is rotatably mounted, and an electrically operated telescopic brush 8 for sweeping the cellulose particles adsorbed on the fiber adsorption membrane onto the glass slide 10. The first sliding pipe 4 is slidably disposed on the oil channel 2.

[0034] Understandably, the insulating support 75 is rotatably mounted on the first sliding pipe 4, ensuring the expansion or folding of the insulating support 75. The rotatable mounting configuration can be of any form well known to those skilled in the art.

[0035] Suitable but not limiting, the fiber collection mechanism further includes a second sliding conduit 3 slidable on the inner wall of the oil passage 2, the second sliding conduit 3 being used to press the insulating support 75 into a fully extended state when it slides to a position where the first sliding conduit 4 is located between the second sliding conduit 3 and the inner wall of the oil passage 2.

[0036] Here, the fully extended position can be, for example, a horizontal orientation, meaning that the extension direction of the insulating support 75 is generally perpendicular to the sliding direction of the second sliding pipe 3, i.e., the axial direction of the oil passage 2.

[0037] Optionally, the fiber collection mechanism further includes a support 7 for picking up the fiber adsorption membrane supported by the insulating support 75 after the insulating support 75 is pressed to a fully extended state.

[0038] In order to achieve the matching of the pick-up position of the support 7 with the fiber adsorption membrane, the support 7 can be configured to move in a lifting or horizontal manner.

[0039] Suitable but not limiting, the fiber collection mechanism also includes an insulating sealing ring 6 fixed on the oil passage 2 to limit the sliding position of the second sliding pipe 3.

[0040] To accommodate the fiber adsorption membrane, a fiber adsorption membrane box 1 can be provided so that the insulating support 5 can be replenished in a timely manner after a single fiber adsorption membrane is consumed.

[0041] The fiber adsorption membrane box 1 can be positioned directly above the insulating support 5, so that the fiber adsorption membrane discharged from the fiber adsorption membrane box 1 will automatically fall onto the insulating support 5 under its own weight after being discharged.

[0042] refer to Figure 3 The aforementioned online fiber particle monitoring mechanism includes an optical fiber transmitter 20, an optical fiber receiving probe 21, an A / D signal conversion unit, a signal processing unit, and a fiber particle counting display. The optical fiber transmitter 20 and the optical fiber receiving probe are installed on the front and rear sides of the device. The optical fiber receiving probe 21 is connected to the A / D signal conversion unit, which converts the optical signal into an electrical signal and transmits it to the signal processing unit. The signal processing unit is connected to the fiber particle counting display.

[0043] The aforementioned fiber dispersion characteristic analysis mechanism includes a fiber spreading rod 9, a glass slide capable of linear reciprocating motion 10, a processing liquid container 11, a refractive index liquid container 12, a miniature automatic polarizing mirror 22, an automatic focusing camera 13, a data storage device 14, and a white light source 15.

[0044] Fiber spreading rod 9 repeatedly rolls the fibers on the moving slide 10, ensuring the fibers are evenly spread on the slide. The moving slide 10 carrying the fibers then slowly passes through a treatment liquid container 11 containing a treatment liquid (e.g., n-hexane) to degrease the fibers and remove insulating oil and impurities. Subsequently, a refractive index liquid container 12 containing refractive index liquid is added in an appropriate amount based on the size of the fiber area on the moving slide. After the white light source 15 is automatically turned on, a miniature polarizer and an autofocus camera 13 automatically focus. Under the illumination of the white light source 15, the miniature polarizer acts as an optical path for the refracting fibers of the cellulose particles on the slide 10, thus obtaining the dispersed colors of the cellulose particles. The autofocus camera 13 is installed at the position aligned with the miniature polarizer, thereby obtaining the dispersed image of the cellulose particles and thus a set of dispersed colors from different fibers.

[0045] Furthermore, the alarm mechanism includes an alarm 16 and a flashlight 17; the collected fiber dispersion color is matched with the polymerization degree of insulating paper with different aging degrees and the corresponding dispersion color of the fiber in the data storage 14 to determine the aging state of the insulating paper in the transformer. When the polymerization degree is lower than 250, the alarm 16 is triggered, and the flashlight 17 flashes continuously.

[0046] Furthermore, the power supply mechanism includes a solar panel 18 and a battery 19; the solar panel 18 is connected to the battery 19, and the battery 19 is connected to the bus head of this device to provide power.

[0047] This example provides an online aging detection device for insulating paper based on fiber collection and dispersion characteristic analysis. The device first requires constructing a relationship spectrum between the degree of polymerization of the insulating paper and the dispersion characteristics of detached fibers through numerous experiments, storing this spectrum in a data storage device. The specific implementation steps are as follows:

[0048] First, connect the solar panel 18 to the battery 19, and then connect the battery 19 to the bus connector of the online detection device 24 for power supply. Next, install the online detection device 24 between the transformer 25 and the oil tank 23. When fiber particles suspended in the insulating oil flow through the oil channels, they block the intensity of the optical fiber emitted by the fiber transmitter 20, changing the reception rate of the fiber receiver probe 21. Furthermore, the fiber adsorption film on the fan-shaped insulating support 5 in the oil channels adsorbs the fiber particles. The fiber receiver probe 21 transmits the optical signal to the A / D signal conversion unit, which converts the received optical signal into an electrical signal and transmits it to the signal processing unit. After processing, the number of fiber particles is displayed on the counting display.

[0049] When the number of fiber particles exceeds a preset value, the fiber dispersion characteristic analysis mechanism is triggered. At this time, the insulating support 5 slowly retracts, closely adhering to the first sliding pipe 4. Subsequently, the second sliding pipe 3 slides downwards, stopping upon contact with the insulating sealing ring 6. At this point, the second sliding pipe 3 completely overlaps with the first sliding pipe 4 that fixes the insulating support 5. Then, the first sliding pipe 4 that fixes the insulating support 5 moves upwards towards the outer wall of the oil passage 2, and the insulating support 5 unfolds horizontally. An interlaced support 7 on the inner wall of the device slowly rises, supporting the fiber collection and adsorption membrane, and rises to the top of the device. The insulating support on the second sliding pipe 3... As the frame 5 retracts and fits tightly against the pipe, the staggered supports 7 slide the collected fiber adsorption membrane down to the bottom of the device and slowly brush the fiber onto the glass slide 10 via the electric telescopic brush 8. At this time, the insulating support 5 on the second sliding pipe 3 re-expands horizontally, and the fiber adsorption membrane box 1 above the device will drop a new fiber adsorption membrane downwards. After the insulating support 5 fixes the adsorption membrane, it begins to retract and fit tightly against the second sliding pipe 3. The first sliding pipe 4, which is attached to the outer wall of the oil passage 2, moves down until it overlaps with the second sliding pipe 3. Then, the second sliding pipe 3 moves up along the inner wall of the oil passage, and the fiber adsorption membrane on the insulating support 5 re-expands in a fan shape.

[0050] The fiber-laden glass slide 10 is first repeatedly rolled by the fiber spreading rod 9 to evenly spread the fibers on the moving carrier slide 10. Then, the slide 10 is slowly passed through the processing liquid container 11 to degrease the fibers and remove insulating oil and impurities. Subsequently, a suitable amount of refractive index liquid is dripped into the refractive index liquid container 12 according to the size of the fiber area on the moving carrier slide 10. After the white light source 15 is turned on, the miniature automatic polarizer 22 and the automatic focusing camera 13 automatically focus and record the dispersion color of the fibers after dispersion in the camera. The slide 10 continuously fine-tunes its position to obtain a set of different fiber dispersion colors. The collected fiber dispersion colors are matched with the dispersion color relationship spectrum of insulating paper with different aging degrees and detached fibers in the data storage 14 to determine the aging state of the insulating paper inside the transformer 25. When the polymerization degree is lower than 250, the alarm 16 is triggered, and the flashlight 17 flashes continuously to remind the staff to repair the transformer 25 in time.

[0051] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. An online aging detection device for insulating paper based on fiber collection and dispersion characteristic analysis, characterized in that, include: An online monitoring mechanism for cellulose particles includes an optical fiber transmitter, an optical fiber receiving probe, an A / D signal conversion unit, and a signal processing unit. The optical fiber transmitter generates emitted light that acts on insulating oil. The optical fiber receiving probe receives the emitted light from the optical fiber transmitter and acts on by the insulating oil, converting it into an analog electrical signal. The A / D signal conversion unit converts the analog electrical signal from the optical fiber receiving probe into a digital electrical signal. The signal processing unit processes the digital electrical signal into readable data. A fiber collection mechanism is used to collect cellulose particles by adsorbing insulating oil through a fiber adsorption membrane; A fiber dispersion characteristic analysis mechanism is used to analyze the dispersion color parameters of cellulose particles collected by the fiber collection mechanism in order to determine the aging degree of the insulating paper corresponding to the insulating oil. The fiber collection mechanism includes an insulating support for supporting the fiber adsorption membrane, a first sliding pipe on which the insulating support is rotatably mounted, and an electrically operated telescopic brush for sweeping the cellulose particles adsorbed on the fiber adsorption membrane onto a glass slide. The first sliding pipe is slidably disposed on an oil channel. The fiber collection mechanism also includes a second sliding pipe that can slide on the inner wall of the oil passage. The second sliding pipe is used to press the insulating support into a fully extended state when it slides to a position where the first sliding pipe is located between the second sliding pipe and the inner wall of the oil passage. The fiber collection mechanism also includes a support for picking up the fiber adsorption membrane supported by the insulating support after the insulating support is pressed to a fully extended state. The fiber dispersion characteristic analysis mechanism includes a fiber spreading rod, a glass slide capable of linear reciprocating motion, a processing liquid container, a refractive liquid container, a miniature automatic polarizing mirror, and a white light source. The fiber spreading rod is used to roll the fibers on the glass slide, the processing liquid container is used to drop the processing liquid onto the glass slide, the refractive liquid container is used to drop the refractive liquid onto the glass slide, and the miniature automatic polarizing mirror is used to collect the dispersion color parameters of the cellulose particles on the glass slide under the illumination of the white light source. The fiber dispersion feature analysis mechanism also includes an autofocus camera for taking pictures of the dispersion color images collected by the miniature automatic polarizer; The fiber dispersion feature analysis mechanism also includes a data storage device for storing preset images of the degree of polymerization of insulating paper and the dispersion color of cellulose particles at different aging levels. The online cellulose particle monitoring mechanism also includes a cellulose particle counting display electrically connected to the signal processing unit. The cellulose particle counting display is used to display readable cellulose particle related parameters; when the number of cellulose particles exceeds a preset value, the fiber dispersion characteristic analysis mechanism is triggered.

2. The online aging detection device for insulating paper according to claim 1, characterized in that, The fiber collection mechanism also includes an insulating sealing ring fixed on the oil passage to limit the sliding position of the second sliding pipe.

3. The online aging detection device for insulating paper according to claim 1, characterized in that, It includes an alarm mechanism that triggers an alarm when the aging of the insulation paper inside the transformer exceeds a preset aging level.

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